Yeah, and even in the fic I referenced, it wasn't meant as a kink, but as a way of humiliating the one on the receiving end.
That actually makes sense. (Even if it does still kinda squick me out.)
Actually, I may have seen that. Was the mech in question Starscream?

There was a bunny not long ago about the implications of mechs with windscreens in their chests, since that is the location of a Cybertronian's spark. I likened it to wearing a bikini - revealing without actually showing everything, which is amusing when you consider that it implies that Optimus Prime goes about in the Cybertronian equivalent of a bikini... and for that matter so do Ironhide and Ratchet in G1.
Well, when you think about it, Alpha-Trion designed Optimus... I'm amused... Ooh, Blaster and Soundwave too! Mmmm...

I think if that is used as the basic measuring stick, then the Seekers, with their chest canopies and bitch heels are "dressed" like they're in bikini tops and slutty high heel boots. XD
*Loves* I so wanna see a pic of the seekers as prostitutes now... (And Soundwave or Megatron as their pimp... hahaha... What a great mental image...)
(Megatron: You have failed me. AGAIN. Get out there and earn, Starscream!)

Suffice to say, it'd give my poor Maggy a nervous breakdown, methinks. He'd probably be so happy once he gets back to his own 'verse that he'd even hug Megatron. (BTW, in the RP Maggy is muse for, Megatron is his brother-in-law.)
Poor guy. *Hugs UM* Brother-in-law... so by marriage? Who's married to who? (Sorry that I'm nosy...)